55 results on '"Francesco Botrè"'
Search Results
2. Variability of the urinary and blood steroid profiles in healthy and physically active women with and without oral contraception
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Basile Moreillon, Olivier Salamin, Bastien Krumm, Loredana Iannella, Francesco Molaioni, Tiia Kuuranne, Raul Nicoli, Jonas J. Saugy, Francesco Botrè, and Raphael Faiss
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Pharmaceutical Science ,Environmental Chemistry ,Spectroscopy ,Analytical Chemistry - Abstract
The steroidal module of the athlete biological passport (ABP) targets the use of pseudo-endogenous androgenous anabolic steroids in elite sport by monitoring urinary steroid profiles. Urine and blood samples were collected weekly during two consecutive oral contraceptive pill (OCP) cycles in 15 physically active women to investigate the low urinary steroid concentrations and putative confounding effect of OCP. In urine, testosterone (T) and epitestosterone (E) were below the limit of quantification of 1 ng/ml in 62% of the samples. Biomarkers' variability ranged between 31% and 41%, with a significantly lesser variability for ratios (except for T/E [41%]): 20% for androsterone/etiocholanolone (p 0.001) and 25% for 5α-androstane-3α,17β-diol/5ß-androstane-3α,17β-diol (p 0.001). In serum, markers' variability (testosterone: 24%, androstenedione: 23%, dihydrotestosterone: 19%, and T/A4: 16%) was significantly lower than in urine (p 0.001). Urinary A/Etio increased by18% after the first 2 weeks (p 0.05) following withdrawal blood loss. In contrast, serum T (0.98 nmol/l during the first week) and T/A4 (0.34 the first week) decreased significantly by more than 25% and 17% (p 0.05), respectively, in the following weeks. Our results outline steroidal variations during the OCP cycle, highlighting exogenous hormonal preparations as confounder for steroid concentrations in blood. Low steroid levels in urine samples have a clear negative impact on the subsequent interpretation of steroid profile of the ABP. With a greater analytical sensitivity and lesser variability for steroids in healthy active women, serum represents a complementary matrix to urine in the ABP steroidal module.
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- 2022
3. Indirect biomarkers of blood doping: a systematic review
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Bastien, Krumm, primary, Saugy Jonas, J., additional, Francesco, Botrè, additional, Francesco, Donati, additional, and Raphael, Faiss, additional
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- 2023
- Full Text
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4. LC‐HRMS‐based metabolomics workflow: An alternative strategy for metabolite identification in the antidoping field
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Patrizia Leogrande, Daniel Jartdines, Dayamin Martinez‐Brito, Xavier de la Torre, Maria Kristina Parr, and Francesco Botrè
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Organic Chemistry ,Spectroscopy ,Analytical Chemistry - Published
- 2023
5. Urinary Excretion of Ecdysterone and Its Metabolites Following Spinach Consumption
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Tasha Yuliandra, Konstantina Touvleliou, Xavier de la Torre, Francesco Botrè, Steffen Loke, Eduard Isenmann, Sarah Valder, Patrick Diel, and Maria Kristina Parr
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Food Science ,Biotechnology - Published
- 2023
6. Evaluation of longitudinal 13 C isotope ratio mass spectrometric data in antidoping analysis
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Xavier de la Torre, Daniel Jardines, and Francesco Botrè
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Pharmaceutical Science ,Environmental Chemistry ,Spectroscopy ,Analytical Chemistry - Published
- 2022
7. Correction of the urinary testosterone to epitestosterone ratio measurement in antidoping analyses by chromatographic and mass spectrometric techniques
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Dayamín Martínez Brito, Teresa Correa Vidal, Xavier de la Torre, Rodny Montes de Oca Porto, and Francesco Botrè
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Pharmaceutical Science ,Environmental Chemistry ,Spectroscopy ,Analytical Chemistry - Published
- 2023
8. Thyroid metabolism and supplementation: A review framed in sports environment
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Dayamin Martínez Brito, Francesco Botrè, Francesco Romanelli, and Xavier de la Torre
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Doping in Sports ,Athletes ,Dietary Supplements ,Thyroid Gland ,Humans ,Pharmaceutical Science ,Environmental Chemistry ,Spectroscopy ,Sports ,Analytical Chemistry - Abstract
This paper aimed to consider those features that may suggest a link between thyroid hormones pharmacology and athletes' health based on current consumption trends in a population of athletes.Methods used were observation, description, and synthesis, mainly. Among the documents reviewed were books, scientific articles, and review articles peer-reviewed. The review covered sources published in the period 1961 to 2021. Only references with a traceable origin were accepted (DOI numbering, ISSN, and ISBN, as well as peer-reviewed journals). The data on the consumption of thyroid hormones derivatives were extracted from the Doping Control Forms of athlete samples received at Laboratorio Antidoping FMSI of Rome from 2017 to 2021.An overview of the biosynthesis, pharmacology, and metabolism of thyroid hormones, including thyronamines and thyronacetic acids, was presented. Likewise, a summary is presented on the relationship between thyroid hormones and ethnic and gender differences, their physiology in sport, and the reasons why their use could be considered attractive for athletes.Today, thyroid hormones are not listed as a prohibited substance by the World Anti-Doping Agency. However, several requests to include levothyroxine on the prohibited list are documented. The observation that the number of athletes taking thyroid hormones is growing, particularly in sports such as cycling, triathlons, and skating, should prompt an update on this topic.
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- 2022
9. In vitro metabolic profile of mexedrone, a mephedrone analog, studied by high‐ and low‐resolution mass spectrometry
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Fabio De-Giorgio, Xavier de la Torre, Monica Mazzarino, Matteo Marti, Angelica Guglielmelli, Francesco Botrè, and Cristian Camuto
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Cathinone ,Mexedrone ,Socio-culturale ,Pharmaceutical Science ,Mass spectrometry ,Tandem mass spectrometry ,Methamphetamine ,Analytical Chemistry ,Hydroxylation ,chemistry.chemical_compound ,Tandem Mass Spectrometry ,medicine ,Humans ,Environmental Chemistry ,LS7_5 ,Chromatography, High Pressure Liquid ,Spectroscopy ,LS7_9 ,Chromatography ,mexedrone ,synthetic cathinones ,Chemistry ,in vitro metabolism ,mephedrone analogs ,novel psychoactive substances ,Triple quadrupole mass spectrometer ,Metabolome ,Microsomes, Liver ,Microsome ,Drug metabolism ,medicine.drug - Abstract
Mexedrone is a synthetic cathinone structurally related to mephedrone, which belongs to the class of N-alkyl cathinone derivatives, whose metabolic profile has not been fully clarified yet. This study considers the in vitro phase I metabolism of mexedrone, to pre-select the most appropriate marker(s) of intake. Mexedrone was incubated in the presence of either human liver microsomes or single recombinant CYP450 isoforms. The metabolic profile was outlined by ultra-high-performance liquid chromatography coupled to both high- and low-resolution mass spectrometry. In detail, the phase I metabolic profile of mexedrone was initially defined by a time-of-flight analyzer, while the chemical structures of the detected metabolites and the potential presence of minor metabolites were subsequently studied by tandem mass spectrometry, using a triple quadrupole analyzer. The main phase I metabolic reactions were hydroxylation and N- and O-dealkylation. The CYP450 isoforms most involved were CYP2C19, responsible for the formation of both hydroxylated and dealkylated metabolites, followed by CYP2D6 and CYP1A2, involved in the hydroxylation reactions only. Finally, a significant fraction of mexedrone unchanged was also detected. Based on this evidence, the most appropriate markers of intake are mexedrone unchanged and the hydroxylated metabolites.
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- 2021
10. Effects of the administration of miconazole by different routes on the biomarkers of the 'steroidal module' of the Athlete Biological Passport
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Francesco Botrè, Monica Mazzarino, Xavier de la Torre, Francesco Molaioni, and Fabio Comunità
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Adult ,Male ,Time Factors ,Miconazole ,Administration, Oral ,Pharmaceutical Science ,Pharmacology ,Administration, Cutaneous ,Gas Chromatography-Mass Spectrometry ,Analytical Chemistry ,Young Adult ,chemistry.chemical_compound ,Deglucuronidation ,Tandem Mass Spectrometry ,athletes biological passport ,medicine ,Humans ,Environmental Chemistry ,confounding factors ,antidoping analysis ,Research Articles ,Spectroscopy ,Testosterone ,Doping in Sports ,Androsterone ,Etiocholanolone ,business.industry ,Epitestosterone ,Administration, Buccal ,steroidal module ,Buccal administration ,Middle Aged ,chemistry ,Athletes ,Systemic administration ,Steroids ,business ,Biomarkers ,Chromatography, Liquid ,Research Article ,medicine.drug - Abstract
This article reports the results obtained from the investigation of the influence of miconazole administration on the physiological fluctuation of the markers of the steroid profile included in the “steroidal module” of the Athlete Biological Passport. Urines collected from male Caucasian subjects before, during, and after either systemic (i.e., oral and buccal) or topical (i.e., dermal) treatment with miconazole were analyzed according to validated procedures based on gas chromatography coupled to tandem mass spectrometry (GC–MS/MS) (to determine the markers of the steroid profile) or liquid chromatography coupled to MS/MS (LC–MS/MS) (to determine miconazole urinary levels). The results indicate that only after systemic administration, the markers of the steroid profile were significantly altered. After oral and buccal administration, we have registered (i) a significant increase of the 5α‐androstane‐3α,17β‐diol/5β‐androstane‐3α,17β‐diol ratio and (ii) a significant decrease of the concentration of androsterone, etiocholanolone, 5β‐androstane‐3α,17β‐diol, and 5α‐androstane‐3α,17β‐diol and of the androsterone/etiocholanolone, androsterone/testosterone, and 5α‐androstane‐3α,17β‐diol/epitestosterone ratios. Limited effects were instead measured after dermal intake. Indeed, the levels of miconazole after systemic administration were in the range of 0.1–12.5 μg/ml, whereas after dermal administration were below the limit of quantification (50 ng/ml). Significant alteration started to be registered at concentrations of miconazole higher than 0.5 μg/ml. These findings were primarily explained by the ability of miconazole in altering the kinetic/efficacy of deglucuronidation of the endogenous steroids by the enzyme β‐glucuronidase during the sample preparation process. The increase of both incubation time and amount of β‐glucuronidase was demonstrated to be effective countermeasures in the presence of miconazole to reduce the risk of uncorrected interpretation of the results., The results obtained from the investigation of the influence of miconazole administration on the parameters included in the “steroidal module” of the Athlete Biological Passport were presented. After oral and buccal administration of miconazole, the levels of the markers of the steroid profile were significantly altered, whereas no effects were registered after topical administration. These findings were primarily explained by the effect of miconazole on the kinetics/efficacy of the enzymatic hydrolysis during the sample preparation process.
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- 2021
11. Detection of clostebol in sports: Accidental doping?
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Francesco Molaioni, Francesco Botrè, Michele Iannone, Daniel Jardines, Xavier de la Torre, and Cristiana Colamonici
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Male ,Skin Absorption ,Metabolite ,Skin Cream ,Pharmaceutical Science ,Physiology ,Administration, Cutaneous ,01 natural sciences ,Analytical Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Anabolic Agents ,0302 clinical medicine ,CLOSTEBOL ACETATE ,Humans ,Environmental Chemistry ,Medicine ,Testosterone ,030216 legal & forensic medicine ,Spectroscopy ,Doping in Sports ,business.industry ,010401 analytical chemistry ,Clostebol ,Neomycin ,Mass spectrometric ,0104 chemical sciences ,Drug Combinations ,Italy ,chemistry ,Female ,Physiological fluid ,business ,medicine.drug - Abstract
The detection of clostebol misuse in sports has been growing recently, especially in Italy, due to the ample availability of pharmaceutical formulations containing clostebol acetate (Trofodermin®) and the use of more sensitive instrumentation by the antidoping laboratories. Most of these cases have been claimed to be related to a nonconscious use of the drug or through contact with relatives or teammates using it. We have investigated, through the application of the well-known and currently used gas chromatographic mass spectrometric procedures, the likelihood of these allegations and have demonstrated that after a single transdermal administration of 5 mg of clostebol acetate and a transient contact with the application area, it is possible to generate adverse analytical findings in antidoping controls. We have reviewed the Phase I and Phase II clostebol metabolism in order to generate evidences that may help the sport authorities reviewing these cases. The main clostebol metabolite (4-chloro-androst-4-en-3α-ol-17-one, M1) generally used at the screening level as well as other three metabolites (M2-M4) are mainly excreted as glucuronides, whereas M5 (4ζ-chloro-5ζ-androstan-3β-ol-17-one) is predominantly excreted as sulfate. Neither the 5α-reductases activity (impaired by the presence of the chlorine in C4) nor specific sulfotransferases present in the skin allowed a clear distinction of the administration route. Studies with a larger number of volunteers and probably investigating another physiological fluid allowed in antidoping such as blood are needed for a deeper investigation. It is not unreasonable to establish a reporting level for M1, maybe creating some false negatives but excluding nonintentional doping scenarios.
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- 2020
12. Development and validation of a liquid chromatography–tandem mass spectrometry method for the simultaneous analysis of androgens, estrogens, glucocorticoids and progestagens in human serum
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Michele Iannone, Anna Pia Dima, Francesca Sciarra, Francesco Botrè, and Andrea M. Isidori
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Pharmacology ,Clinical Biochemistry ,Reproducibility of Results ,Estrogens ,General Medicine ,Biochemistry ,Analytical Chemistry ,Tandem Mass Spectrometry ,Drug Discovery ,Androgens ,Humans ,Steroids ,Progestins ,Glucocorticoids ,Molecular Biology ,Chromatography, High Pressure Liquid ,Chromatography, Liquid - Abstract
We present a liquid chromatography tandem mass spectrometry method for the simultaneous analysis of 16 endogenous steroids (androgens, estrogens, glucocorticoids and progestogens) in human serum. Samples (250 μl of matrix) were extracted with t-butylmethyl ether prior to LC-MS/MS analysis. The chromatographic separation was achieved on a reversed-phase column using a methanol-water gradient. The HPLC was coupled to a triple quadrupole mass spectrometer equipped with an electrospray ionization source with acquisition in multiple reaction monitoring mode. The method was validated using surrogate matrices and human serum samples. The specificity of the method was confirmed for all of the considered steroids; linearity was also assessed (R
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- 2022
13. Carbon isotopic characterization of prednisolone and prednisone pharmaceutical formulations: Implications in antidoping analysis
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Francesco Botrè, Loredana Iannella, Xavier de la Torre, Cristiana Colamonici, Chiara Ciccarelli, Davide Curcio, and Monica Mazzarino
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Adult ,Male ,Drug Compounding ,Prednisolone ,medicine.medical_treatment ,Administration, Oral ,Pharmaceutical Science ,Urine ,Tandem mass spectrometry ,01 natural sciences ,High-performance liquid chromatography ,Gas Chromatography-Mass Spectrometry ,Analytical Chemistry ,Young Adult ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,Humans ,Environmental Chemistry ,030216 legal & forensic medicine ,Isotope-ratio mass spectrometry ,Administration, Intranasal ,Spectroscopy ,Doping in Sports ,Carbon Isotopes ,Chromatography ,010401 analytical chemistry ,0104 chemical sciences ,Substance Abuse Detection ,chemistry ,Nasal spray ,Pregnanediol ,Prednisone ,Female ,Gas chromatography ,medicine.drug - Abstract
Twenty-two pharmaceutical formulations containing prednisolone or prednisone commercially available in Italy, Belgium, Spain, Brazil, and India were analyzed through a specific gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS) method. All of them showed typical non-endogenous δ13 C values, except for the Belgian nasal spray, Sofrasolone®, with a less depleted 13 C content (-17.84 ± 0.18‰). Observational studies were performed on two volunteers in therapy with Sofrasolone® to confirm the applicability of the method and to suggest adequate interpretation criteria also in the case of drugs with less negative δ13 C values. Urine samples were collected before, during, and within the 36 hours after the administration of the spray. Both δ13 C values and urinary concentrations of prednisolone and prednisone were evaluated. All samples were subjected to an adequate pre-treatment (enzymatic hydrolysis, liquid/liquid extraction, and two sequential HPLC steps) before injection to the GC-C-IRMS instrument, according to the method recently developed and validated in our laboratory. Pregnanediol (PD), tetrahydro-11-deoxycortisol (THS), and pregnanetriol (PT) were selected as endogenous reference compounds (ERC). The excretion profile was estimated through liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) method used routinely for the quali-quantitative detection of glucocorticoids. δ13 C values and urinary levels of prednisolone and prednisone were also determined after the intake of one single vial of Sintredius®, a prednisolone oral formulation with a conventional more negative δ13 C value (-29.28 ± 0.25‰). Finally, the potential masking effect that combined therapy with Sofrasolone® and Sintredius® could induce on the IRMS findings was investigated.
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- 2020
14. Metabolomics workflow as a driven tool for rapid detection of metabolites in doping analysis. Development and validation
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Patrizia Leogrande, Daniel Jardines, Maria Kristina Parr, X. de la Torre, Francesco Botrè, Dayamin Martinez-Brito, and E. Domenici
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Multivariate analysis ,business.industry ,Chemistry ,Organic Chemistry ,Pattern recognition ,Mass spectrometry ,Rapid detection ,Analytical Chemistry ,Metabolomics ,Low energy ,Workflow ,Healthy volunteers ,Artificial intelligence ,business ,Spectroscopy ,High potential - Abstract
RATIONALE This work demonstrated the high potential of combining high-resolution mass spectrometry with chemometric tools, using metabolomics as a guided tool for anti-doping analysis. The administration of 7-keto-DHEA was studied as a proof-of-concept of the effectiveness of the combination of knowledge-based and machine-learning approaches to differentiate the changes due to the athletic activities from those due to the recourse to doping substances and methods. METHODS Urine samples were collected from 5 healthy volunteers before and after an oral administration by identifying three-time intervals. Raw data were acquired by injecting less than one microliter of derivatized samples into an Agilent Technologies 8890 Gas Chromatograph coupled to an Agilent Technologies 7250 Accurate-Mass Quadrupole Time-of-Flight, by using a low energy electron ionization source, and then they were preprocessed to align peak retention times with the same accurate mass. The resulting data table was subjected to multivariate analysis. RESULTS Multivariate analysis showed a high similarity between the samples belonging to the same collection interval and a clear separation between the different excretion intervals. The discrimination between blank and long excretion groups may suggest the presence of long excretion markers, which are particularly significant in anti-doping analysis. Furthermore, matching the most significant features with some of the metabolites reported in the literature data demonstrated the rationality of the proposed metabolomics-based approach. CONCLUSIONS The application of metabolomics tools as an investigation strategy could reduce the time and resources required to identify and characterize intake markers maximizing the information that can be extracted from the data and extending the research field by avoiding a priori bias. Therefore, metabolic fingerprinting of prohibited substance intakes could be an appropriate analytical approach to reduce the risk of false-positive/negative results, aiding in the interpretation of "abnormal" profiles and discrimination of pseudo-endogenous steroid intake in the anti-doping field.
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- 2021
15. Author response for 'Metabolomics workflow as a driven tool for rapid detection of metabolites in doping analysis. Development and validation'
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Maria Kristina Parr, Daniel Jardines, Francesco Botrè, Dayamin Martinez-Brito, X. Torre, E. Domenici, and Patrizia Leogrande
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Workflow ,Metabolomics ,business.industry ,Computer science ,Software engineering ,business ,Rapid detection - Published
- 2021
16. Low‐energy electron ionization optimization for steroidomics analysis using high‐resolution mass spectrometry
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Maria Kristina Parr, Francesco Botrè, Dayamin Martinez-Brito, Daniel Jardines, Patrizia Leogrande, and Xavier de la Torre
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Fragmentation (mass spectrometry) ,Chemistry ,Design of experiments ,Organic Chemistry ,Polyatomic ion ,Analytical chemistry ,Gas chromatography ,Factorial experiment ,Ionization energy ,Mass spectrometry ,Spectroscopy ,Electron ionization ,Analytical Chemistry - Abstract
RATIONALE Systematic electron ionization fragmentation studies of steroids have been performed to elucidate and trace their characteristic fragmentation patterns. However, the electron ionization source setting at 70 eV electron energy is much higher than the ionization potential (7-15 eV) of most organic compounds, leading to extensive fragmentation. We present a multifactorial study on optimizing a low-energy electron ionization source to maximize molecular ion formation while minimizing the extent of fragmentation to improve the analytical sensitivity of steroids, especially the more thermolabile ones, while preserving the information that can be extracted from the data. METHODS Twenty-seven steroid reference materials, chosen to cover four main classes of urinary steroids, were considered; gas chromatography/quadrupole time-of-flight (GC/qTOF) analyses were carried out using an Agilent Technologies model 8890 gas chromatograph coupled to an Agilent Technologies model 7250 accurate-mass quadrupole time-of-flight (GC/qTOF) instrument. The effects of electron energy, emission current, and source temperature, as well as their potential interactions on steroid fragmentation pathways, have been assessed in full factorial experimental designs. RESULTS Three parameters were specifically evaluated to improve the chromatographic/spectrometric response of the selected steroids: (i) degree of fragmentation; (ii) relative abundance of the molecular ion; and (iii) peak width. The first two were evaluated by screening designs that highlighted collision energy and source temperature as the most influential factors on the analytical responses of the considered steroids, while emission current always showed a non-significant influence. Then, an optimization design was performed to select the final source setting by searching for the combination of factors that minimize peak tailing. CONCLUSIONS The proposed analytical approach permits a faster selection of optimal experimental conditions for steroidomics analysis using low-energy electron ionization and high-resolution mass spectrometry. The development of these designs of experiments (DoE) in full factorial design (FFD) allowed multiple inputs to be monitored at the same time, highlighting the possible interactions and estimating the effects of a factor in the different levels of the other factors considered.
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- 2021
17. Author response for 'Low‐energy electron ionization optimization for steroidomics analysis using high‐resolution mass spectrometry'
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D. M. Brito, Maria Kristina Parr, Daniel Jardines, X. Torre, Patrizia Leogrande, and Francesco Botrè
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Low energy ,Materials science ,Analytical chemistry ,Electron ionization - Published
- 2021
18. Improving the Detection of Homologous Blood Transfusion in Sport Doping: A Full DNA‐based Genotyping Strategy on Dried Blood Spots
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Francesco Donati, Alice Natalucci, Xavier de la Torre, and Francesco Botrè
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chemistry.chemical_compound ,Spots ,Homologous blood ,Chemistry ,Genetics ,Dried blood ,Molecular Biology ,Biochemistry ,Genotyping ,Molecular biology ,DNA ,Biotechnology - Published
- 2021
19. The effect of human genetic variability on basal values of serum and urine biomarkers: implications in anti‐doping analysis
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Francesco Botrè, Livia Concetti, Francesco Donati, and Xavier de la Torre
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medicine.medical_specialty ,Basal (phylogenetics) ,Endocrinology ,Urine biomarkers ,Chemistry ,Internal medicine ,Genetics ,medicine ,Genetic variability ,Molecular Biology ,Biochemistry ,Biotechnology - Published
- 2021
20. An investigation on the metabolic pathways of synthetic isoflavones by gas chromatography coupled to high accuracy mass spectrometry
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Michele Iannone, Silvia Parenti, Francesco Botrè, Xavier de la Torre, and Daniel Jardines
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Adult ,Male ,Anabolism ,Urine ,Mass spectrometry ,01 natural sciences ,Gas Chromatography-Mass Spectrometry ,Mass Spectrometry ,Analytical Chemistry ,chemistry.chemical_compound ,Anabolic Agents ,Oral administration ,medicine ,Humans ,Spectroscopy ,Doping in Sports ,Chromatography ,010401 analytical chemistry ,Organic Chemistry ,Isoflavones ,0104 chemical sciences ,Metabolic pathway ,chemistry ,Gas chromatography ,Ipriflavone ,Metabolic Networks and Pathways ,medicine.drug - Abstract
Rationale Isoflavones are a group of flavonoids that may be of interest in sport doping because they can be used by athletes in the recovery periods after the administration of anabolic steroids, with the aim of increasing the natural production of luteinizing hormone (LH) and, consequently, the biosynthesis of endogenous androgens. Methods The in vivo metabolism of methoxyisoflavone (5-methyl-7-methoxyisoflavone) and ipriflavone (7-isopropoxyisoflavone), respectively present in a dietary supplement and in a pharmaceutical preparation, was investigated. The study was carried out by the analysis of urinary samples collected from male Caucasian subjects before, during and after the oral administration of methoxyisoflavone or ipriflavone. After enzymatic hydrolysis and liquid-liquid extraction, all urinary samples were analyzed by gas chromatography/quadrupole time-of-flight (qTOF MS system/qTOF) electron ionization mass spectrometry (EI-MS). Results Eight metabolites of methoxyisoflavone and six metabolites of ipriflavone were isolated. The corresponding accurate mass spectra are specific for isoflavone structures and revealed also a retro-Diels-Alder fragmentation. Conclusions When excreted in large amounts, the urinary metabolites of methoxyisoflavone and ipriflavone can be traced to potential confounding factors in doping analysis. As methoxyisoflavone and ipriflavone have been shown to inhibit the enzyme aromatase, thus interfering with the normal metabolic pathways of testosterone, the detection of their intake, by screening for the presence of their main metabolites in urine, might be helpful in routine doping control analysis.
- Published
- 2019
21. Author response for 'Detection of urinary arimistane metabolites in humans by liquid chromatography mass spectrometry. Complementary results to gas chromatography mass spectrometric data and its application to antidoping analyses'
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Patrizia Leogrande, Xavier de la Torre, Francesco Botrè, and Dayamin Martinez Brito
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Chromatography ,Chemistry ,Liquid chromatography–mass spectrometry ,Gas chromatography ,Mass spectrometric - Published
- 2021
22. Author response for 'In‐depth GC‐MS/MS Fragmentation Analysis of Formestane and Evaluation of Mass Spectral Discrimination of Isomeric 3‐Keto‐4‐ene Hydroxy Steroids'
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Christian Müller, Francesco Botrè, Xavier de la Torre, Annette Sophie Kollmeier, and Maria Kristina Parr
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Fragmentation (mass spectrometry) ,Chemistry ,medicine ,Gas chromatography–mass spectrometry ,Medicinal chemistry ,Formestane ,Ene reaction ,medicine.drug - Published
- 2020
23. Mass spectrometric analysis of 7‐oxygenated androst‐5‐ene structures. Influence in trimethylsilyl derivative formation
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Dayamin Martinez-Brito, Francesco Botrè, Maria Kristina Parr, and Xavier de la Torre
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Analyte ,Chromatography ,Trimethylsilyl ,010401 analytical chemistry ,Organic Chemistry ,Mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Matrix (chemical analysis) ,chemistry.chemical_compound ,chemistry ,Reagent ,Gas chromatography ,Derivatization ,Spectroscopy ,Ene reaction - Abstract
Several authors have described the generation of androsta-3,5-diene-7-one structures from androst-5-ene-3,7-dione or androst-5-ene-3β-ol-7-one under acidic conditions and/or at high temperatures. The goal of this study was to observe and to describe the results obtained after the chromatographic analysis of the trimethylsilyl derivatives of reference materials of 7-oxo-DHEA, 7α-hydroxy-DHEA, 7β-hydroxy-DHEA, and androsta-3,5-diene-7,17-dione known as arimistane. Methods The purity of the analyte reference materials was verified by liquid chromatography/quadrupole mass spectrometry. The trimethylsilyl derivatives obtained using several mixtures with MSTFA (N-methyl-N-trimethylsilyl trifluoroacetamide) in comparison with solely MSTFA were analyzed by gas chromatography coupled to a time-of-flight detector equipped with a multimode inlet or to a simple quadrupole detector with a split/splitless inlet. Results The study showed that the formation of arimistane from 7-oxo-DHEA occurs using common derivatization reagents used for the analyses by gas chromatography (GC). In addition, the formation of the enolized TMS derivative of 7-oxo-DHEA was observed in considerable amount when it was reacted with MSTFA. The analysis of 7α-hydroxy-DHEA resulted in the detection of ~1% of arimistane. The formation of unexpected artifacts from derivatization is influenced by the reagent itself, the reaction temperature, the inlet used and its configuration. Conclusions The derivatization reagent, instrumental conditions (inlet), as well as the chemical structures of the analytes present in the matrix, can influence the results. So, before describing a new feature as a potential "new" metabolite, special caution must be taken since we could actually be dealing with an artifact.
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- 2020
24. Author response for 'A further insight on methyltestosterone metabolism: new evidences from in vitro and in vivo experiments'
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Francesco Molaioni, M.A. Tatangelo, Francesco Botrè, Michele Iannone, X. de la Torre, and Dayamin Martinez-Brito
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In vivo ,Chemistry ,medicine ,Metabolism ,Pharmacology ,Methyltestosterone ,In vitro ,medicine.drug - Published
- 2020
25. Author response for 'Mass spectrometric analysis of 7‐oxygenated androst‐5‐ene structures. Influence in trimethylsilyl derivatives formation'
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Dayamin Martinez-Brito, Maria Kristina Parr, Francesco Botrè, and Xavier de la Torre
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chemistry.chemical_compound ,Trimethylsilyl ,chemistry ,Organic chemistry ,Mass spectrometric ,Ene reaction - Published
- 2020
26. Effect of non-prohibited drugs on the phase II metabolic profile of morphine. An in vitro investigation for doping control purposes
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Francesco Botrè, Maria Kristina Parr, Gabriella Ambrosio, Monica Mazzarino, and Xavier de la Torre
- Subjects
Ketoprofen ,drug-drug interactions ,Antifungal Agents ,Triazolam ,anti-doping analysis ,masking strategy ,morphine ,Pharmaceutical Science ,In Vitro Techniques ,Pharmacology ,030226 pharmacology & pharmacy ,01 natural sciences ,Analytical Chemistry ,Benzodiazepines ,03 medical and health sciences ,0302 clinical medicine ,Tandem Mass Spectrometry ,medicine ,Humans ,Environmental Chemistry ,Drug Interactions ,Glucuronosyltransferase ,Spectroscopy ,Bromazepam ,Morphine ,Chemistry ,Anti-Inflammatory Agents, Non-Steroidal ,010401 analytical chemistry ,Lorazepam ,Lormetazepam ,0104 chemical sciences ,Substance Abuse Detection ,Alprazolam ,Microsomes, Liver ,Ketoconazole ,Chromatography, Liquid ,medicine.drug ,Nimesulide - Abstract
The potential consequences of drug-drug interaction on the strategies adopted by anti-doping laboratories to report an adverse analytical finding for morphine were investigated. We evaluated in vitro the effects of 14 drugs on the principal metabolic pathways of morphine. The selected drugs are among those most commonly used by the athletes, none of them presently included in the World Anti-Doping Agency (WADA) Prohibited List. The non-prohibited drugs included 4 antifungals (fluconazole, itraconazole, ketoconazole, and miconazole), 6 benzodiazepines (alprazolam, bromazepam, clonazepam, lorazepam, lormetazepam, and triazolam), and 4 non-steroidal anti-inflammatory drugs (diclofenac, ibuprofen, ketoprofen, and nimesulide). The in vitro assays were based on the use of either human liver microsomes or uridine 5'-diphospho-glucuronosyl-transferases. Morphine and its glucuronides were determined by developed liquid chromatography-mass spectrometry procedure after dilution with an aqueous solution containing their deuterated isotopologues as internal standards. Morphine is mainly excreted as phase II metabolites: about 70% of the parent compound is found to be biotransformed by UGT2B7 to morphine-3-glucuronide (6065%) and morphine-6-glucuronide (5-10%). A reduction of the enzymatic activity of the UGT2B7 was recorded in the presence of 9 of the 14 drugs under investigation (ketoconazole, miconazole, itraconazole, diclofenac, ibuprofen, clonazepam, lorazepam, lormetazepam, and triazolam), with a consequent significant reduction of the levels of the glucuronide metabolites. This phenomenon in vivo may affect the rate of the urinary excretion of morphine with the risk of reporting "false negative" results, especially in case of results close to the decision limit value set by WADA.
- Published
- 2018
27. Longitudinal evaluation of the isotope ratio mass spectrometric data: towards the ‘isotopic module’ of the athlete biological passport?
- Author
-
Francesco Botrè, Davide Curcio, Xavier de la Torre, Cristiana Colamonici, Gemma Procida, and Daniel Jardines
- Subjects
Chromatography ,Isotope ,Chemistry ,010401 analytical chemistry ,Pharmaceutical Science ,030229 sport sciences ,01 natural sciences ,Mass spectrometric ,0104 chemical sciences ,Analytical Chemistry ,03 medical and health sciences ,0302 clinical medicine ,Environmental Chemistry ,Gas chromatography–mass spectrometry ,Isotope-ratio mass spectrometry ,Spectroscopy - Abstract
The detection of the abuse of pseudo-endogenous steroids (testosterone and/or its precursors) is currently based on the application of the steroid module of the World Anti-Doping Agency (WADA) Athletes' Biological Passport (ABP), implemented through ADAMS. Diagnostic metabolites are monitored for every athlete and statistically evaluated with a predictive Bayesian approach. In the case of suspicious samples, the data of the ABP are confirmed and the isotope ratio mass spectrometry (IRMS) test is activated. We have previously demonstrated that IRMS enables confirmation of the non-endogenous origin of pseudo-endogenous steroids in otherwise non-suspicious samples, after a longitudinal evaluation of the ABP, even after the inclusion of additional long-term diagnostic hydroxylated metabolites, and that the delta values of the parameters obtained during the IRMS confirmation process presented much less variability compared to the parameters of the ABP. The aim of the present work is to evaluate the application of the same methodology used for the evaluation of the ABP, on the delta values of the pseudo-endogenous steroids monitored. The effectiveness of the proposed model has been assessed on samples obtained after controlled administrations of oral androstenedione and transdermal testosterone. The results support the conclusion that, if applied, the longitudinal evaluation of the IRMS data allows the detection of positive samples that otherwise will be reported as atypical findings (ATF), improving the efficacy of the fight against doping in sport. This approach, by narrowing the individual acceptable range, could possibly improve the detection of the intake of preparations of synthetic origin with delta values close to or overlapping those of endogenously produced steroids. Copyright © 2016 John Wiley & Sons, Ltd.
- Published
- 2016
28. Doping control container for urine stabilization: a pilot study
- Author
-
Dimitrios G. Georgakopoulos, Peter Van Eenoo, Xavier de la Torre, Koen Deventer, Wim Van Gansbeke, K. Roels, Fiona Hooghe, Evangelia Giannadaki, Francesco Botrè, Maria Tsivou, Costas Georgakopoulos, Monica Mazzarino, Flaminia Garribba, Francesco Donati, and Emmanouil Lyris
- Subjects
Routine screening ,Chromatography ,Urinalysis ,medicine.diagnostic_test ,Chemistry ,010401 analytical chemistry ,Proteolytic enzymes ,Pharmaceutical Science ,Urine ,010402 general chemistry ,Antimicrobial ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Matrix (chemical analysis) ,Small peptide ,medicine ,Environmental Chemistry ,Glucuronide ,Spectroscopy - Abstract
Urine collection containers used in the doping control collection procedure do not provide a protective environment for urine, against degradation by microorganisms and proteolytic enzymes. An in-house chemical stabilization mixture was developed to tackle urine degradation problems encountered in human sport samples, in cases of microbial contamination or proteolytic activity. The mixture consists of antimicrobial substances and protease inhibitors for the simultaneous inactivation of a wide range of proteolytic enzymes. It has already been tested in lab-scale, as part of World Anti-Doping Agency's (WADA) funded research project, in terms of efficiency against microbial and proteolytic activity. The present work, funded also by WADA, is a follow-up study on the improvement of chemical stabilization mixture composition, application mode and limitation of interferences, using pilot urine collection containers, spray-coated in their internal surface with the chemical stabilization mixture. Urine in plastic stabilized collection containers have been gone through various incubation cycles to test for stabilization efficiency and analytical matrix interferences by three WADA accredited Laboratories (Athens, Ghent, and Rome). The spray-coated chemical stabilization mixture was tested against microorganism elimination and steroid glucuronide degradation, as well as enzymatic breakdown of proteins, such as intact hCG, recombinant erythropoietin and small peptides (GHRPs, ipamorelin), induced by proteolytic enzymes. Potential analytical interferences, observed in the presence of spray-coated chemical stabilization mixture, were recorded using routine screening procedures. The results of the current study support the application of the spray-coated plastic urine container, in the doping control collection procedure. Copyright © 2016 John Wiley & Sons, Ltd.
- Published
- 2016
29. Liposomes as potential masking agents in sport doping. Part 2: Detection of liposome-entrapped haemoglobin by flow cytofluorimetry
- Author
-
Xavier de la Torre, Monica Mazzarino, Francesco Botrè, Francesco Donati, Sonia Colicchia, and Simone Esposito
- Subjects
0301 basic medicine ,Liposome ,Chromatography ,010401 analytical chemistry ,technology, industry, and agriculture ,Pharmaceutical Science ,Conjugated system ,01 natural sciences ,Fluorescence ,0104 chemical sciences ,Analytical Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,chemistry ,Environmental Chemistry ,Fluorescein isothiocyanate ,Haemoglobin-based oxygen carriers ,Ethylene glycol ,Spectroscopy ,Masking agent ,Whole blood - Abstract
This work presents an analytical procedure for the identification and characterization of liposome-entrapped haemoglobins, based on flow cytofluorimetry. Flow cytofluorimetric detection is carried out following labelling by two distinct fluorescent reagents, an anti-haemoglobin antibody, fluorescein isothiocyanate conjugated, and an anti-poly(ethylene glycol) antibody, streptavidin-phycoerythrin conjugated. This experimental strategy allows the detection of liposome-entrapped haemoglobins in aqueous media, including plasma; the efficacy of the proposed approach has been verified on whole blood samples added with the liposomal formulation (ex-vivo). Additionally, the proposed technique allows the characterization of several key parameters in the study of liposomal haemoglobins, including, for instance (1) the determination of the degree of haemoglobin entrapment by liposomes; (2) the poly(ethylene glycol) insertion efficiency; and (3) the evaluation of liposome-entrapped haemoglobins stability following storage at 4 °C, allowing to follow both the process of haemoglobin loss from liposomes and the liposome degradation. The procedure is proposed for the detection and characterization of liposome-entrapped haemoglobin formulations to control their misuse in sport, but is also suggested for further applications in biological and clinical laboratory investigations. Copyright © 2016 John Wiley & Sons, Ltd.
- Published
- 2016
30. Liposomes as potential masking agents in sport doping. Part 1: analysis of phospholipids and sphingomyelins in drugs and biological fluids by aqueous normal-phase liquid chromatography-tandem mass spectrometry
- Author
-
Xavier de la Torre, Francesco Botrè, Simone Esposito, Sonia Colicchia, and Monica Mazzarino
- Subjects
0301 basic medicine ,Liposome ,Chromatography ,010401 analytical chemistry ,Analytical chemistry ,Phospholipid ,Pharmaceutical Science ,Phosphatidic acid ,Tandem mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,chemistry ,Liquid chromatography–mass spectrometry ,Mass spectrum ,Environmental Chemistry ,lipids (amino acids, peptides, and proteins) ,Phosphatidylserines ,Sphingomyelin ,Spectroscopy - Abstract
In the present work, aqueous normal-phase liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), in different acquisition modes, was employed for the direct analysis and profiling of nine phospholipid classes (phosphatidic acids, phosphatidylserines, phosphatidylethanolamines, lysophosphatidylethanolamines, phosphatidylglycerols, phosphatidylinositols, phosphatidylcholines, lysophosphatidylcholines, and sphingomyelins) in biological and pharmaceutical matrices. After chromatographic separation by a diol column, detection and elucidation of phospholipid and sphingomyelin classes and molecular species were performed by different scan acquisition modes. For screening analysis, molecular ions [M + H]+ were detected in positive precursor ion scan of m/z 184 for the classes of phosphatidylcholines, lyso-phosphatidylcholines and sphingomyelins; while phosphatidylethanolamines and lyso-phosphatidylethanolamines were detected monitoring neutral loss scan of 141 Da; and phosphatidylserines detected using neutral loss scan of 184 Da. Molecular ions [M-H]- were instead acquired in negative precursor ion scan of m/z 153 for the classes of phosphatidic acids and phosphatidylglycerols; and of m/z 241 for the phosphatidylinositols. For the identification of the single molecular species, product ion scan mass spectra of the [M + HCOO]- ions for phosphatidylcholines and [M + H]+ ions for the other phospholipids considered were determined for each class and compared with the fragmentation pattern of model phospholipid reference standard. By this approach, nearly 100 phospholipids and sphingomyelins were detected and identified. The optimized method was then used to characterize the phospholipid and sphingomyelin profiles in human plasma and urine samples and in two phospholipid-based pharmaceutical formulations, proving that it also allows to discriminate compounds of endogenous origin from those resulting from the intake of pharmaceutical products containing phospholipidic liposomes. Copyright © 2016 John Wiley & Sons, Ltd.
- Published
- 2016
31. Development and validation of a GC-C-IRMS method for the confirmation analysis of pseudo-endogenous glucocorticoids in doping control
- Author
-
Francesco Botrè, Davide Curcio, Marta Cilia, Xavier de la Torre, Cristiana Colamonici, and Francesco Molaioni
- Subjects
education.field_of_study ,Chromatography ,Population ,Tetrahydrocortisol ,Pharmaceutical Science ,Urine ,High-performance liquid chromatography ,Analytical Chemistry ,chemistry.chemical_compound ,chemistry ,Pregnanediol ,medicine ,Environmental Chemistry ,Tetrahydrocortisone ,Gas chromatography ,Cortisone ,education ,Spectroscopy ,medicine.drug - Abstract
Glucocorticoids are included in the S9 section of the World Anti-doping Agency (WADA) prohibited list international standard. Some among them are pseudo-endogenous steroids, like cortisol and cortisone, which present the same chemical structure as endogenously produced steroids. We are proposing an analytical method based on gas chromatography coupled to isotope ratio mass spectrometry (GC-C-IRMS) which allows discrimination between endogenous and synthetic origin of the urinary metabolites of the pseudo-endogenous glucocorticoids. A preliminary purification treatment by high-performance liquid chromatography (HPLC) of the target compounds (TC) (i.e., cortisol, tetrahydrocortisone (THE) 5α-tetrahydrocortisone (aTHE), tetrahydrocortisol (THF), and 5α-tetrahydrocortisol (aTHF)) allows collection of extracts with adequate purity for the subsequent analysis by IRMS. A population of 40 urine samples was analyzed for the TC and for the endogenous reference compounds (ERC: i.e., 11-desoxy-tetrahydrocortisol (THS) or pregnanediol). For each sample, the difference between the delta values of the ERCs and TCs (Δδ values) were calculated and based on that, some decision limits for atypical findings are proposed. The limits are below 3% units except for cortisol. The fit to purpose of the method has been confirmed by the analysis of urine samples collected in two patients under treatment with 25 mg of cortisone acetate (p.o). The samples showed Δδ values higher than 3 for at least 24 h following administration depending on the TC considered. The method can easily be integrated into existing procedures already used for the HPLC purification and IRMS analysis of pseudo-endogenous steroids with androgenic/anabolic activity.
- Published
- 2015
32. Corticosteroid Biosynthesis Revisited: Substrate Specificity of Steroid 21‐Hydroxylase
- Author
-
Maria Kristina Parr, Xavier de la Torre, Jan Felix Joseph, Gerhard Wolber, Matthias Bureik, Steffen Loke, David Machalz, Anna Stoll, and Francesco Botrè
- Subjects
medicine.medical_specialty ,Steroid 21-Hydroxylase ,Chemistry ,medicine.drug_class ,Biochemistry ,chemistry.chemical_compound ,Endocrinology ,Biosynthesis ,Internal medicine ,Genetics ,medicine ,Corticosteroid ,Substrate specificity ,Molecular Biology ,Biotechnology - Published
- 2020
33. Myokines as potential indirect biomarkers of myostatin abuse in sport doping: reference ranges in elite athletes
- Author
-
Francesco Donati, Francesco Noce, Veronica Sian, Francesco Botrè, Giorgia Morgan Biasini, Lavinia Rutigliano, Alba Lasalvia, and Xavier de la Torre
- Subjects
biology ,business.industry ,Myokine ,Genetics ,biology.protein ,Medicine ,Elite athletes ,Myostatin ,business ,Molecular Biology ,Biochemistry ,Biotechnology ,Clinical psychology - Published
- 2020
34. Transcranial direct current stimulation and sport performance: Brain Derived Neurotrophic Factor and neurotrophins as potential biomarkers of abuse
- Author
-
Francesco Donati, Xavier de la Torre, Giorgia Morgan Biasini, Francesco Botrè, Lavinia Rutigliano, and Veronica Sian
- Subjects
Brain-derived neurotrophic factor ,Transcranial direct-current stimulation ,biology ,business.industry ,medicine.medical_treatment ,Biochemistry ,Potential biomarkers ,Genetics ,medicine ,biology.protein ,business ,Molecular Biology ,Neuroscience ,Biotechnology ,Neurotrophin - Published
- 2020
35. In vitroevaluation of the effects of anti-fungals, benzodiazepines and non-steroidal anti-inflammatory drugs on the glucuronidation of 19-norandrosterone: implications on doping control analysis
- Author
-
Ilaria Fiacco, Francesco Botrè, Xavier de la Torre, Beatrice Alessi, Amelia Palermo, and Monica Mazzarino
- Subjects
Triazolam ,Metabolite ,Electrospray ionization ,010401 analytical chemistry ,Selected reaction monitoring ,Glucuronidation ,Pharmaceutical Science ,Pharmacology ,Tandem mass spectrometry ,030226 pharmacology & pharmacy ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,chemistry ,medicine ,Environmental Chemistry ,Glucuronide ,19-Norandrosterone ,Spectroscopy ,medicine.drug - Abstract
We have studied whether the phase II metabolism of 19-norandrosterone, the most representative metabolite of 19-nortestosterone (nandrolone), can be altered in the presence of other drugs that are not presently included on the Prohibited List of the World Anti-Doping Agency. In detail, we have evaluated the effect of non-prohibited drugs belonging to the classes of anti-fungals, benzodiazepines, and non-steroidal anti-inflammatory drugs on the glucuronidation of 19-norandrosterone. In vitro assays based on the use of either pooled human liver microsomes or specific recombinant isoforms of uridine diphosphoglucuronosyl-transferase were designed and performed to monitor the formation of 19-norandrosterone glucuronide from 19-norandrosterone. Determination of 19-norandrosterone (free and conjugated fraction) was performed by gas chromatography - mass spectrometry after sample pretreatment consisting of an enzymatic hydrolysis (performed only for the conjugated fraction), liquid/liquid extraction with tert-butylmethyl ether, and derivatization to form the trimethylsilyl derivative. In parallel, a method based on reversed-phase liquid chromatography coupled to tandem mass spectrometry in positive electrospray ionization with acquisition in selected reaction monitoring mode was also developed to identify the non-prohibited drugs considered in this study. Incubation experiments have preliminarily shown that the glucuronidation of 19-norandrosterone is principally carried out by UGT2B7 (39%) and UGT2B17 (31%). Inhibition studies have shown that the yield of the glucuronidation reaction is reduced in the presence of the anti-fungals itraconazole, ketoconazole, and miconazole, of the benzodiazepine triazolam and of the non-steroidal anti-inflammatory drugs diclofenac and ibuprofen, while no alteration was recorded in the presence of all other compounds considered in this study. Copyright © 2015 John Wiley & Sons, Ltd.
- Published
- 2015
36. Detection of formestane abuse by mass spectrometric techniques
- Author
-
Davide Curcio, Daniel Jardines, Maria Kristina Parr, Francesco Molaioni, Francesco Botrè, Xavier de la Torre, and Cristiana Colamonici
- Subjects
Chromatography ,Chemistry ,medicine ,Pharmaceutical Science ,Environmental Chemistry ,Analytical strategy ,Isotope-ratio mass spectrometry ,Mass spectrometry ,Mass spectrometric ,Formestane ,Spectroscopy ,Analytical Chemistry ,medicine.drug - Abstract
Formestane (4-hydroxy-androstenedione) is an aromatase inhibitor prohibited in sports and included, since 2004, in the list of prohibited substances updated yearly by the World Anti-Doping Agency (WADA). Since the endogenous production of formestane has been described, it is mandatory for the anti-doping laboratories to use isotope ratio mass spectrometry (IRMS) to establish the exogenous origin before issuing an adverse analytical finding. The described IRMS methods for formestane detection are time-consuming, requiring usually two consecutive liquid chromatographic sample purifications in order to have final extracts of adequate purity before the mass spectrometric analysis. After establishing a procedure for the determination of the origin of formestane by IRMS without the need of derivatization, and integrated in the overall analytical strategy of the laboratory for pseudo-endogenous steroids, a mass spectrometric analysis by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS) of formestane metabolites was carried out in order to investigate whether other biomarkers of formestane abuse could be integrated in order to avoid time-consuming and expensive IRMS confirmations for formestane. From the metabolic studies performed, the inclusion of 3β,4α-dihydroxy-5α-androstan-17-one (4α-hydroxy-epiandosterone) in the routine GC-MS procedures has demonstrated to be diagnostic in order to reduce the number of unnecessary confirmations of the endogenous origin of formestane.
- Published
- 2014
37. Drug-drug interaction and doping, part 2: Anin vitrostudy on the effect of non-prohibited drugs on the phase I metabolic profile of stanozolol
- Author
-
Monica Mazzarino, Ilaria Fiacco, Francesco Botrè, and Xavier de la Torre
- Subjects
Chemistry ,Phase (matter) ,Doping ,Drug-drug interaction ,medicine ,Pharmaceutical Science ,Environmental Chemistry ,Pharmacology ,Spectroscopy ,Metabolic profile ,Stanozolol ,Analytical Chemistry ,medicine.drug - Published
- 2014
38. Metabolism of methylstenbolone studied with human liver microsomes and the uPA+/+-SCID chimeric mouse model
- Author
-
Leen Lootens, Koen Deventer, Francesco Botrè, Vinod Nair, Peter Van Eenoo, Michaël Polet, Lore Geldof, Daniel Eichner, Philip Meuleman, Geert Leroux-Roels, and Thane Campbell
- Subjects
Pharmacology ,Chromatography ,Chemistry ,medicine.medical_treatment ,Clinical Biochemistry ,General Medicine ,Metabolism ,Biochemistry ,In vitro ,Analytical Chemistry ,Methasterone ,Steroid ,In vivo ,Drug Discovery ,medicine ,Microsome ,Gas chromatography–mass spectrometry ,Molecular Biology ,Drug metabolism ,medicine.drug - Abstract
Anti-doping laboratories need to be aware of evolutions on the steroid market and elucidate steroid metabolism to identify markers of misuse. Owing to ethical considerations, in vivo and in vitro models are preferred to human excretion for nonpharmaceutical grade substances. In this study the chimeric mouse model and human liver microsomes (HLM) were used to elucidate the phase I metabolism of a new steroid product containing, according to the label, methylstenbolone. Analysis revealed the presence of both methylstenbolone and methasterone, a structurally closely related steroid. Via HPLC fraction collection, methylstenbolone was isolated and studied with both models. Using HLM, 10 mono-hydroxylated derivatives (U1-U10) and a still unidentified derivative of methylstenbolone (U13) were detected. In chimeric mouse urine only di-hydroxylated metabolites (U11-U12) were identified. Although closely related, neither methasterone nor its metabolites were detected after administration of isolated methylstenbolone. Administration of the steroid product resulted mainly in the detection of methasterone metabolites, which were similar to those already described in the literature. Methylstenbolone metabolites previously described were not detected. A GC-MS/MS multiple reaction monitoring method was developed to detect methylstenbolone misuse. In one out of three samples, previously tested positive for methasterone, methylstenbolone and U13 were additionally detected, indicating the applicability of the method.
- Published
- 2014
39. Metabolism of boldione in humans by mass spectrometric techniques: detection of pseudoendogenous metabolites
- Author
-
Xavier de la Torre, Cristiana Colamonici, Francesco Molaioni, Francesco Botrè, and Davide Curcio
- Subjects
Chromatography ,medicine.medical_treatment ,Metabolite ,Pharmaceutical Science ,Boldenone ,High-performance liquid chromatography ,Analytical Chemistry ,Steroid ,Hydroxylation ,chemistry.chemical_compound ,chemistry ,medicine ,Environmental Chemistry ,Gas chromatography ,Isotope-ratio mass spectrometry ,Boldione ,Spectroscopy ,medicine.drug - Abstract
Boldione is an anabolic androgenic steroid (AAS) related to boldenone, androstenedione, and testosterone bearing two double bonds in C1 and C4 positions. Boldione is rapidly transformed to the well-known AAS boldenone, being both compounds included in the list of prohibited substances and methods published yearly by the World Anti-Doping Agency (WADA). After the administration of boldione to a male volunteer, the already described urinary metabolites of boldenone produced after reduction in C4, oxydoreduction in C3 and C17, and hydroxylation have been detected. In addition, minor new metabolites have been detected and their structure postulated after mass spectrometric analyses. Finally, the reduction of the double bound in C1 produces metabolites identical to the endogenously produced ones. A method based on gas chromatography coupled to isotope ratio mass spectrometry (GC/C/IRMS) after a urine sample purification by high performance liquid chromatography (HPLC) permitted to confirm the main synthetic like boldione/boldenone metabolite (17β-hydroxy-5β-androst-1-en-3-one) and boldenone at trace levels (< 5 ng/mL) and then to establish its synthetic or endogenous origin, and to determine the exogenous origin of metabolites with the same chemical structure of the endogenous ones. The detection of pseudoendogenous androgens of synthetic origin partially overlapped boldenone and its main metabolite detection, being an additional proof of synthetic steroids misuse. By the use of IRMS, the correct evaluation of the modifications of the steroid profile after the administration of synthetic AAS that could be converted into endogenous like ones is possible. Copyright © 2013 John Wiley & Sons, Ltd.
- Published
- 2013
40. Smoking habits of italian athletes undergoing anti-doping control
- Author
-
Ilaria Palmi, Simona Pichini, Francesco Botrè, Xavier de la Torre, and Roberta Pacifici
- Subjects
medicine.medical_specialty ,biology ,Athletes ,Smoking habit ,business.industry ,010401 analytical chemistry ,Pharmaceutical Science ,biology.organism_classification ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,03 medical and health sciences ,0302 clinical medicine ,Physical therapy ,medicine ,Environmental Chemistry ,030212 general & internal medicine ,Young adult ,business ,Spectroscopy - Published
- 2015
41. A rapid analytical method for the detection of plasma volume expanders and mannitol based on the urinary saccharides and polyalcohols profile
- Author
-
Monica Mazzarino, Ilaria Fiacco, Francesco Botrè, and Xavier de la Torre
- Subjects
Detection limit ,Analyte ,Chromatography ,Pharmaceutical Science ,Urine ,Maltose ,Hydroxyethyl starch ,Isomaltose ,Analytical Chemistry ,chemistry.chemical_compound ,chemistry ,Enzymatic hydrolysis ,medicine ,Environmental Chemistry ,Mannitol ,Spectroscopy ,medicine.drug - Abstract
A screening procedure specifically developed for the detection of saccharides and polyalcohols in human urine in the framework of doping control analysis is presented. The proposed method, set-up, and validated to detect the abuse of dextran, hydroxyethyl starch and mannitol as a doping practice in sport, involves only one enzymatic hydrolysis step and the direct injection into a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system. The chromatographic conditions were optimized to allow the efficient separation of compounds with the same molecular weight. Good linearity (R(2) 0.990-0.995) and reproducibility of relative retention times (CV% lower than 1) and of relative abundances of characteristic ion transitions (CV% lower than 10) were obtained. The lower limits of detection and quantification were in the range of 30-100 µg/ml. Since the analytes studied are present also in non-doping products (e.g. in fruit as well as in food products and drugs additives), the developed method was also used to establish a range of reference urinary concentrations: 600 doping control samples and 30 samples from volunteers not using any medication were considered. While the hydrolysis products (isomaltose and maltose hydroxyl-ethylated), used as specific markers for the detection of dextran and hydroxyethyl starch abuse, were not detected in urine; mannitol was present in all urines in a concentration range of 30-1200 µg/ml. Since no criteria of positivity for mannitol has been established yet, the results obtained in this study could be considered, in combination with those of previous researches, as a starting point to fix a threshold value for doping control purpose.
- Published
- 2011
42. A simple and rapid pre-confirmation method to distinguish endogenous human haemoglobin from synthetic haemoglobin-based oxygen carriers in doping control
- Author
-
Francesco Donati, Francesco Botrè, Monica Mazzarino, Nazia Islam, David A. Cowan, and Xavier de la Torre
- Subjects
Doping in Sports ,Male ,Detection limit ,Chromatography ,Resolution (mass spectrometry) ,Chemistry ,Capillary action ,Clinical Biochemistry ,Analytical chemistry ,Electrophoresis, Capillary ,Reproducibility of Results ,chemistry.chemical_element ,antidoping analysis ,capillary electrophoresis ,dynamic coating ,haemoglobin-based oxygen carriers ,Repeatability ,Biochemistry ,Oxygen ,Analytical Chemistry ,Substance Abuse Detection ,Hemoglobins ,Electrophoresis ,Capillary electrophoresis ,Limit of Detection ,Humans ,Female ,Haemoglobin-based oxygen carriers - Abstract
A specific, sensitive and rapid analytical procedure based on capillary electrophoresis with UV/Vis detection at 405 and 415 nm was developed and validated to detect human haemoglobin and haemoglobin-based oxygen carriers (Hemopure®, Oxyglobin® and Polyheme®) in blood samples collected for doping control. The electrophoretic separation, based on capillary dynamic coating, was achieved in less than 10 min. The effects of capillary temperature, injection conditions and initial ramping were investigated. The optimum separation voltage was 25 kV with a capillary temperature of 20 °C, initial ramping of 1 kV/s and an injection pressure of 0.5 psi for 10 s. The removal of haptoglobin using anti-human haptoglobin antibody prior to the analysis was mandatory to increase the specificity of the analysis. Sufficient resolution between endogenous haemoglobin variants and the three haemoglobin-based oxygen carriers here investigated was obtained, thus allowing discrimination between a normal haemolysed sample and a sample in which Oxyglobin®, Hemopure® or Polyheme® is present. Good repeatability of migration times (CV% less than 1), peak resolution and adequate sensitivity (limit of detection: 2.5 mg/mL) was obtained.
- Published
- 2011
43. Toxicological determination and in vitro metabolism of the designer drug methylenedioxypyrovalerone (MPDV) by gas chromatography/mass spectrometry and liquid chromatography/quadrupole time-of-flight mass spectrometry
- Author
-
Amy B. Cadwallader, Sabina Strano-Rossi, Xavier de la Torre, and Francesco Botrè
- Subjects
Pyrrolidines ,designer drugs ,medicine.drug_class ,Catechols ,Pyrovalerone ,Methylenedioxypyrovalerone ,Glucuronates ,toxicological screening ,Mass spectrometry ,Sensitivity and Specificity ,Gas Chromatography-Mass Spectrometry ,Cell Line ,Analytical Chemistry ,anti-doping analysis ,chemistry.chemical_compound ,LC/QTOF ,Toxicity Tests ,medicine ,Humans ,Benzodioxoles ,forensic toxicology ,methylendioxypyrovalerone (MDPV) ,Spectroscopy ,Detection limit ,Chromatography ,Sulfates ,GC/MS ,Guaiacol ,Organic Chemistry ,Forensic toxicology ,Reproducibility of Results ,Settore MED/43 - MEDICINA LEGALE ,Synthetic Cathinone ,Designer drug ,chemistry ,Microsomes, Liver ,methylendioxypyrovalerone (MDPV), designer drugs, metabolism, toxicological screening, anti-doping analysis, forensic toxicology, GC/MS, LC/QTOF ,Gas chromatography ,Gas chromatography–mass spectrometry ,metabolism ,Chromatography, Liquid ,medicine.drug - Abstract
A method for the toxicological screening of the new designer drug methylenedioxypyrovalerone (MDPV) is described; with an emphasis on its application for anti-doping analysis. The metabolism of MDPV was evaluated in vitro using human liver microsomes and S9 cellular fractions for CYP450 phase I and uridine 5'-diphosphoglucuronosyltransferase (UGT) and sulfotransferase (SULT) phase II metabolism studies. The resulting metabolites were subsequently liquid/liquid extracted and analyzed using gas chromatography/mass spectrometry (GC/MS) as trimethylsilyl (TMS) derivatives. The structures of the metabolites were further confirmed by accurate mass measurement using a liquid chromatography/quadrupole time-of-flight (LC/QTOF) mass spectrometer. The studies demonstrated that the main metabolites of MDPV are catechol and methyl catechol pyrovalerone, which are in turn sulfated and glucuronated. The method for the determination of MDPV in urine has been fully validated by assessing the limits of detection and quantification, linearity, repeatability, and accuracy. This validation demonstrates the suitability for screening of this stimulant substance for anti-doping and forensic toxicology purposes.
- Published
- 2010
44. Improved ultrasonic-based sample treatment for the screening of anabolic steroids by gas chromatography/mass spectrometry
- Author
-
X. de la Torre, J. L. Capelo-Martínez, Raquel Rial-Otero, Francesco Botrè, M. Galesio, and Jesus Simal-Gandara
- Subjects
Chromatography ,Silylation ,Chemistry ,Sonication ,Enzymatic hydrolysis ,Reagent ,Organic Chemistry ,Ultrasonic sensor ,Gas chromatography ,Gas chromatography–mass spectrometry ,Mass spectrometry ,Spectroscopy ,Analytical Chemistry - Abstract
A rapid sample treatment procedure for the gas chromatography/mass spectrometry (GC/MS) determination of anabolic steroids in human urine has been developed. The new procedure makes use of ultrasonic energy to reduce reaction times and increase the overall sensitivity. The following variables affecting the performance of the ultrasonic treatment were optimised: (i) time, (ii) device, (iii) frequency, and (iv) temperature. It was found that, under an ultrasonic field, the hydrolysis of conjugated steroids with β-glucuronidase from Escherichia coli K12 was possible with a treatment time of 10 min. The accuracy and precision of the ultrasonic method were found to be in agreement with those achieved with the conventional thermal conductivity procedure (Student's t-test; p = 0.05, n = 10). After the enzymatic hydrolysis, the derivatisation of the target compounds with trimethylsilyl (TMS) reagent, methyl-N-trimethylsilyltrifluoroacetamide (MSTFA)/NH4I/dithioerythritol (DTE) (1000:2:4, v/w/w), was also accelerated using ultrasonic energy. In order to test the applicability of the use of ultrasonic energy in the acceleration of the derivatisation reaction with TMS, the classic method of thermal conductivity was applied for comparative purposes to a pool of 35 androgenic anabolic steroids (AAS) and/or their metabolites. The results demonstrated that after 3 min of sonication in a Sonoreactor device (50% amplitude), 19 of the 35 compounds studied showed similar reaction yield to those obtained with the classic procedure requiring 30 min (Student's t-test; p = 0.05, n = 5); 13 increased to higher silylation yields; and for the steroids 1-testosterone, danazol and etiocholanolone-D5, the same results were obtained using a sonication time of 5 min. The overall applicability of the ultrasonic-based sample treatment method is shown by the analysis of five urine samples. The results are similar to those achieved by the routine procedure. The new method is fast, robust, and allows high sample throughput. Copyright © 2010 John Wiley & Sons, Ltd.
- Published
- 2010
45. A rapid screening LC-MS/MS method based on conventional HPLC pumps for the analysis of low molecular weight xenobiotics: application to doping control analysis
- Author
-
David A. Cowan, Xavier de la Torre, Nicola Gray, Francesco Botrè, and Monica Mazzarino
- Subjects
Spectrometry, Mass, Electrospray Ionization ,Analyte ,Time Factors ,Electrospray ionization ,Tetrahydrogestrinone ,Pharmaceutical Science ,Urine ,Mass spectrometry ,Tandem mass spectrometry ,High-performance liquid chromatography ,Xenobiotics ,Analytical Chemistry ,anti-doping analysis ,Tandem Mass Spectrometry ,medicine ,Humans ,Environmental Chemistry ,lc-ms/ms ,fused-core particle columns ,Chromatography, High Pressure Liquid ,Spectroscopy ,Doping in Sports ,Detection limit ,Chromatography ,Chemistry ,xenobiotics ,medicine.drug - Abstract
This study presents a fast multi-analyte screening method specifically developed for the detection of xenobiotics in urine. The proposed method allows the screening of several classes of substance in a single chromatographic method with a run-time of 11 min, inclusive of post-run and reconditioning times. Chromatographic separation is achieved in 7.2 min using a reversed-phase 2.7 µm fused-core particle column, generating a back-pressure not exceeding 400 bar and therefore enabling the use of traditional high performance liquid chromatography (HPLC) instruments. The effectiveness of this approach was evaluated, by liquid-chromatography tandem mass spectrometry (LC-MS/MS) in positive electrospray ionization, using 20 blank urine samples spiked with 45 compounds prohibited in sport: 11 diuretics, 16 glucocorticoids, 9 stimulants, 5 anti-oestrogens, as well as formoterol, carboxy-finasteride (previously prohibited by the World Anti-Doping Agency (WADA) in 2008), gestrinone and tetrahydrogestrinone. Qualitative validation shows the proposed method to be specific with no significant interference. All of the analytes considered in this study were clearly distinguishable in urine, with limits of detection ranging from 5 ng/mL to 350 ng/mL, significantly below the Minimum Required Performance Levels (MRPL) set by WADA for the accredited sports anti-doping laboratories. All compounds of interest were separated, including synthetic and endogenous glucocorticoids with similar retention times and fragmentation patterns.
- Published
- 2010
46. A gas chromatography/mass spectrometry method for the determination of sildenafil, vardenafil and tadalafil and their metabolites in human urine
- Author
-
Luca Anzillotti, Sabina Strano-Rossi, Xavier de la Torre, and Francesco Botrè
- Subjects
Chromatography ,Chemistry ,Sildenafil ,Organic Chemistry ,Forensic toxicology ,Urine ,Mass spectrometry ,Tadalafil ,Analytical Chemistry ,chemistry.chemical_compound ,Vardenafil ,medicine ,Gas chromatography ,Gas chromatography–mass spectrometry ,Spectroscopy ,medicine.drug - Abstract
Sildenafil (SDF), vardenafil (VDF) and tadalafil (TDF) are phosphodiesterase type 5 enzyme inhibitors (PDE5Is), used in the treatment of erectile disorders and to improve breathing efficiency in pulmonary hypertension. The increasing incidence of their use among young athletes has drawn the attention of the anti-doping authorities to the possible abuse of PDE5Is by athletes due to their pharmacological activities. This paper describes a method for the determination in urine of PDE5Is and their metabolites by gas chromatography/mass spectrometry (GC/MS) after liquid/liquid extraction of the analytes from urine and derivatisation to obtain trimethylsilyl derivatives. The metabolic profile was studied on real samples collected from subjects taking PDE5Is (Viagra®, Levitra® or Cialis®); the main urinary metabolites were identified and their MS fragmentation characterized. The sample pre-treatment and GC/MS conditions for the detection of the metabolites have been optimised. A method for their preliminary screening and subsequent confirmation is described that takes into account the general requirements of a routine doping analysis to be used for the screening of large numbers of samples. The main metabolites identified can be included in a general purpose screening method and all the metabolites in a more specific confirmation method. The method developed has been applied for the screening of PDE5Is in 5000 urine samples. Based on the obtained results, the proposed method appears to be of practical use in analytical and forensic toxicology, including doping analysis. Copyright © 2010 John Wiley & Sons, Ltd.
- Published
- 2010
47. Rapid screening of beta-adrenergic agents and related compounds in human urine for anti-doping purpose using capillary electrophoresis with dynamic coating
- Author
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Monica Mazzarino, Francesco Botrè, Xavier de la Torre, and Franco Mazzei
- Subjects
Doping in Sports ,Analyte ,Chromatography ,Molecular Structure ,Chemistry ,Capillary action ,Adrenergic beta-Antagonists ,Analytical chemistry ,Electrophoresis, Capillary ,Reproducibility of Results ,Filtration and Separation ,Urine ,Adrenergic beta-Agonists ,Sensitivity and Specificity ,Analytical Chemistry ,Substance Abuse Detection ,Electrophoresis ,Capillary electrophoresis ,Phenols ,Humans ,Sample preparation ,anti-doping analysis ,beta-adrenergic ,capillary electrophoresis ,dynamic capillary coating ,Solid phase extraction ,Amines ,Quantitative analysis (chemistry) - Abstract
This paper presents a capillary electrophoresis method, developed for the detection, in human urine, of beta-adrenergic agents and phenolalkylamines. The electrophoretic separation is achieved in less than 10 min and is based on the use of CEofix kit, for the dynamic capillary coating. The effects of accelerator buffer pH and separation voltage were investigated. The optimum buffer pH was found to be 2.5 for beta2-agonists and 6.2 for beta-blockers and phenoalkylamines with a separation voltage of 15 kV. Urine samples spiked with the compounds here studied were treated according to the standard procedure (SPE and evaporation to dryness) and analyzed by CE interfaced with an UV diode-array, set at 195 and 210 nm. The quantitative validation results, obtained analyzing samples at three different concentrations, show a good precision of peak areas that do not exceed 5% for intra-day assays and 10% for inter-day assays. Good linearity (r(2) > 0.995) was obtained within the 50-500 ng/mL concentration range. The qualitative validation data show a relative migration times (MTs) variation lower than 1%. The analytes were clearly distinguishable in urine, with LOD and LOQ in the range of 10-80 and 40-100 ng/mL, respectively.
- Published
- 2009
48. A fast liquid chromatographic/mass spectrometric screening method for the simultaneous detection of synthetic glucocorticoids, some stimulants, anti-oestrogen drugs and synthetic anabolic steroids
- Author
-
Francesco Botrè and Monica Mazzarino
- Subjects
Doping in Sports ,Detection limit ,Spectrometry, Mass, Electrospray Ionization ,Chromatography ,Chemistry ,Electrospray ionization ,Organic Chemistry ,Selected reaction monitoring ,Estrogen Antagonists ,Tetrahydrogestrinone ,Reproducibility of Results ,Mass spectrometry ,Formestane ,Analytical Chemistry ,Anabolic Agents ,medicine ,Mesocarb ,Humans ,Central Nervous System Stimulants ,Glucocorticoids ,Chromatography, High Pressure Liquid ,Spectroscopy ,Stanozolol ,medicine.drug - Abstract
A fast liquid chromatographic/mass spectrometric (LC/MS/MS) screening method for the detection, in urine, of synthetic glucocorticoids, stimulants (formoterol, modafinil and mesocarb), anti-oestrogens (finasteride, exemestane, anastrozole, letrozole and formestane) and synthetic anabolic steroids (stanozolol, gestrinone and tetrahydrogestrinone) is described. All these drugs (and/or their urinary metabolites) can be simultaneously extracted by a single liquid/liquid extraction step, at alkaline pH, after enzymatic hydrolysis with beta-glucuronidase, and assayed in 7 min by LC/MS/MS using electrospray ionization in positive ion mode and multiple reaction monitoring as the acquisition mode. All compounds show good reproducibility of both the retention times (CV%
- Published
- 2006
49. Drug-drug interaction and doping, part 1: Anin vitrostudy on the effect of non-prohibited drugs on the phase I metabolic profile of toremifene
- Author
-
Amelia Palermo, Francesco Botrè, Monica Mazzarino, Xavier de la Torre, and Ilaria Fiacco
- Subjects
Drug ,Chemistry ,media_common.quotation_subject ,In vitro toxicology ,Pharmaceutical Science ,Pharmacology ,Analytical Chemistry ,medicine ,Environmental Chemistry ,Ketoconazole ,Toremifene ,Miconazole ,Cimetidine ,Nefazodone ,Spectroscopy ,Stanozolol ,medicine.drug ,media_common - Abstract
The present study was designed to provide preliminary information on the potential impact of metabolic drug-drug interaction on the effectiveness of doping control strategies currently followed by the anti-doping laboratories to detect the intake of banned agents. In vitro assays based on the use of human liver microsomes and recombinant CYP isoforms were designed and performed to characterize the phase I metabolic profile of the prohibited agent toremifene, selected as a prototype drug of the class of selective oestrogen receptor modulators, both in the absence and in the presence of medicaments (fluconazole, ketoconazole, itraconazole, miconazole, cimetidine, ranitidine, fluoxetine, paroxetine, nefazodone) not included in the World Anti-Doping Agency list of prohibited substances and methods and frequently administered to athletes. The results show that the in vitro model developed in this study was adequate to simulate the in vivo metabolism of toremifene, confirming the results obtained in previous studies. Furthermore, our data also show that ketoconazole, itraconazole, miconazole and nefazodone cause a marked modification in the production of the metabolic products (i.e. hydroxylated and carboxylated metabolites) normally selected by the anti-doping laboratories as target analytes to detect toremifene intake; moderate variations were registered in the presence of fluconazole, paroxetine and fluoxetine; while no significant modifications were measured in the presence of ranitidine and cimetidine. This evidence imposes that the potential effect of drug-drug interactions is duly taken into account in anti-doping analysis, also for a broader significance of the analytical results.
- Published
- 2014
50. Inhibition-based biosensors for the detection of environmental contaminants: Determination of 2, 4-dichlorophenoxyacetic acid
- Author
-
Claudio Botrè, Francesco Botrè, Franco Mazzei, and Elisabetta Podestà
- Subjects
chemistry.chemical_classification ,Chromatography ,2,4-Dichlorophenoxyacetic acid ,biology ,Chemistry ,Health, Toxicology and Mutagenesis ,technology, industry, and agriculture ,macromolecular substances ,Contamination ,Enzyme assay ,chemistry.chemical_compound ,Enzyme ,Biochemistry ,biology.protein ,Environmental Chemistry ,Electrochemical biosensor ,Alkaline phosphatase ,Glucose oxidase ,Biosensor - Abstract
In this work data are reported on the possibility for detection of environmental contaminants endowed with toxic effects by specifically designed electrochemical biosensors. A new bienzymatic inhibition biosensor based on the combined catalytic activity of the enzymes alkaline phosphatase and glucose oxidase is proposed and discussed for the direct determination of 2, 4-dichloro-phenoxyacetic acid (2, 4-D), one of the most powerful and diffused defoliants, which also is endowed with estrogenic properties. A discussion on the different approaches followed to manage the experimental data obtained by enzymatic inhibition biosensors is also presented.
- Published
- 2000
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